1. Technical Field
The present invention relates to a tape cartridge installed on the cartridge installation portion of a tape printing apparatus to be used and subjected to printing by the tape printing apparatus.
2. Background Art
Up until now, a tape cassette installed in a printing apparatus to be used has been known as such a tape cartridge. See Japanese Patent No. 3629823.
The tape cassette includes a tape supplying reel on which a printing tape is wound, a ribbon supplying reel on which an ink ribbon is wound, a ribbon winding-up reel that winds up the ink ribbon, and a cassette casing that accommodates these constituents.
On the other hand, the printing apparatus includes a cassette cover at the upper surface of an apparatus main body and a cassette accommodation portion, on which the tape cassette is detachably installed, inside the cassette cover. In the cassette accommodation portion, a printing head, a platen roller, a tape supplying shaft, and a ribbon winding-up shaft are disposed in their standing state. When the tape cassette is installed on the cassette accommodation portion, the tape supplying shaft and the ribbon winding-up shaft are inserted in the tape supplying reel and the ribbon winding-up reel, respectively.
The platen roller is rotatably attached to a U-shaped supporting member via a shaft. In addition, the supporting member is rotatably attached to a chassis via a supporting shaft. The supporting member rotates with the closing of the cassette cover and comes in contact with the printing head. On the other hand, the printing head is fixed to the chassis via a protection member. An engagement projection is provided to stand on the upper surface of the protection member and engages with an interval restriction member provided to freely rise and fall on the upper end surface of the chassis. That is, with the interval restriction member, the tape cassette is structured to restrict the interval between the upper end of the printing head and that of the platen roller at a constant interval. Thus, the printing head and the upper end of the platen roller are prevented from relatively separating from each other at printing and brought into uniformly press-contact with each other to attain an improvement in printing quality.
In such a known printing apparatus, the interval restriction member is provided to maintain the uniform press-contact between the printing head and the platen roller. This results in the problem that the structure of this portion becomes complicated. In addition, it is required to insert the printing tape and the ink ribbon between the printing head and the platen roller at the installation of the tape cassette. Therefore, it is required to rise and fall the interval restriction member is required for the attachment/detachment of the tape cassette, which results in the problem that an operation becomes complicated.
The present invention has an object of providing a tape cartridge that allows the platen supporting shaft of a tape printing apparatus to be supported at both ends thereof with a simple structure and a simple operation.